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The Video Tool Library (VTL) is one of the major normative components of the Reconfigurable Video Coding (RVC) standard. It specifies the set of functional units (FUs) that may be interchangeably combined and connected to form different video codecs, with various compression performances and implementation complexities. In this paper, an efficient AVC baseline encoder that is described in CAL is introduced. The encoder is composed of many modules that also exist in other codecs of the same or different standards. This makes them highly reusable within the RVC framework. The main modules of the designed encoder include: Inter Prediction, Intra Prediction, and Entropy Coding. Brief descriptions of the designed modules, accompanied with CAL design issues are provided.

This paper describes a stereoscopic imaging algorithm that is modified for obstacle detection in low flying unmanned aerial vehicles (UAVs). In this type of flight, obstacle detection must be carried out quickly for the system to be effective in real time. Additionally, since the aircraft is close to the ground, the horizon is usually at the top of the field of view and obstacles must be distinguished from the clutter of the terrain. The sparse edge detection and reconstruction algorithm proposed, produces fast but partial reconstructions of the environment. One image is passed through a series of edge detectors to generate a very sparse outline of the environment. This outline is then correlated to the second image and the resulting reconstruction is added to a model of the environment. Although each individual reconstruction is incomplete, the overall result after a short initialization period is a model of the environment that is more comprehensive than a single stereoscopic correlation run with a more detailed edge detector. Simulation of the algorithm on test image patterns showed an increase in performance relative to the length of the sequence of stereo pairs. On average, the signal to noise ratio (SNR) for sparse edge reconstruction was significantly higher than that for single correlation with more detailed edge detectors. Additionally it was found that the processing speed of the sparse edge detection algorithm on a pair of stereoscopic images is faster than the processing carried out by a more detailed edge detector. A test flight was also carried out to test the algorithm in a more realistic scenario. The test confirmed that the sparse edge reconstruction algorithm resulted in a much more detailed view of the environment than if a single, more detailed edge detector had been used.

This paper presents the design and fabrication of 1600V 4H-SiC UMOSFETs with a novel dual buffer layer structure, which shortens the trench etching time by 2/spl times/ and achieves a high channel periphery density of 3330cm/cm/sup 2/ for low specific on-resistance. The device exhibits 50m/spl Omega/-cm/sup 2/ of specific on-resistance with /spl sim/1/spl mu/m of channel length, and could be further reduced with

This paper describes a SiC-based motor drive technology used to achieve compact power conversion. The static and dynamic characterization of 600 V SiC MOS-enhanced JFETs and SiC Schottky free-wheeling diodes (FWDs) designed and fabricated at Rockwell Scientific, are performed. The power loss and related voltage and current stress of the SiC MOS-enhanced JFET and SiC Schottky FWD are measured and compared to that of a state-of-the-art silicon IGBTs and PlN FWDs with ratings equal to the SiC ratings. For the same power rating (25 A, 600 V), the area of the SiC die making up the inverter modules are about 60% of a commercial 25 A IGBT die. The total power loss of SiC inverter module is reduced by 52.5% compared with the Si IGBT module. SiC inverter modules are used to successfully drive 10 hp motor.

A design method for a suspended substrate stripline bandpass filter with one transmission zero at a given frequency is presented. We use a generalized Chebychev lowpass prototype based on admittance inverters and parallel resonators. The filter topology is called "Capacitive gap-parallel coupled line filter" because the synthesis is based on the equivalent circuits of parallel-coupled lines and end-coupled (gap) lines. A CAD software has been developed for the synthesis of such suspended substrate filters and a prototype filter at 8.5 GHz is given as an example.

A new SiC-based motor drive technology is described to achieve compact power conversion. The static and dynamic characterization of 600V SiC MOS-enhanced JFETs and SiC Schottky free-wheeling diodes (FWDs) designed and fabricated at Rockwell Scientific, were performed and packaged into inverter modules with a voltage rating of 600V and current carrying capabilities of 5A, 10A, and 25A, respectively. For the same power rating (25A, 600V), the size of the SiC inverter module is smaller than that of the Si module by 50%. The SiC inverter modules are used to drive the motors of 1hp to 10hp successfully. This is the first time that motor drive using SiC inverter modules is demonstrated.

This paper describes a new SiC-based motor drive technology used to achieve compact power conversion. The static and dynamic characterization of 600 V SiC MOS-enhanced JFETs and SiC Schottky free-wheeling diodes (FWDs) designed and fabricated at Rockwell Scientific, are performed. Single 5 A SiC JFET and Schottky FWD die with a voltage rating of 600 V are paralleled to obtain 10 A, and 25 A, current ratings. The power loss and related voltage and current stress of the SiC MOS-enhanced JFET and SiC Schottky FWD are measured and compared to that of a state-of-the-art silicon IGBTs and PIN FWDs with ratings equal to the SiC ratings. For the same power rating (25 A, 600 V), the area of the SiC die making up the inverter module are about 60% of a commercial 25 A IGBT die. The Rockwell Automation RA Model 1336 motor controller is used, with its gate drive circuit modified to control the SiC depletion-mode MOS-enhanced JFETs, to control a motor. SiC inverter modules are fabricated and used to successfully drive 1 hp to 10 hp motors. To our knowledge, this is the first time that a motor drive using SiC inverter modules has been demonstrated.